Tap changers are used for controlling the output voltage of a transformer by providing the possibility of switching in or switching out additional turns in a transformer winding. A tap changer comprises a set of fixed contacts which are connectable to a number of taps of a regulating winding of a transformer, where the taps are located at different positions in the regulating winding. A tap changer further comprises a moveable contact which is connected to a current collector at one end, and connectable to one of the fixed contacts at the other end. By switching in or out the different taps, the effective number of turns of the transformer can be increased or decreased, thus regulating the output voltage of the transformer. Tap changers are generally customized for a particular application, especially when the tap changer is intended for higher transformer voltage ratings. Thus, each high voltage tap changer design is typically produced in very small volumes only. The design of the tap changer, as well as the adaptation of the manufacturing process, is time consuming.